The present invention relates to a method of determining a fire guidance or control solution when a relative movement exists between a weapon that fires a projectile, and which is movable in azimuth and elevation, and a target object that is to be hit or struck.
The fire guidance solution refers to the pairs of values of azimuth angle α and elevation angle ε that are to be set and with which the projectile point of impact coincides adequately precisely with the location of the target object at the same point in time after the projectile flight time.
The starting point of the invention is the difficulty of determining the point of impact and the flight time of a projectile that has been fired from a weapon that is movable in azimuth and elevation, i.e. of solving the so-called movement differential equations of the extra ballistic. In this connection, the projectile point of impact and the projectile flight time depend not only on the azimuth angle and elevation angle that have been set, but also upon the ammunition used and further influences, such as the wind or the temperature. Due to the number and uncertainty of the parameters, it is generally not possible to calculate the projectile point of impact and the projectile flight time. For this reason, various movement differential equation solution methods are used, such as, for example, the numeric integration, the use of firing diagrams, or approximations. Of particular prominence is the NATO Armaments Ballistic Kernel (NABK), which, using the inputparameters such as azimuth angle, elevation angle, ammunition and weather data determines the flight path of the projectile as a function of time [x(t), y(t), z(t)].
The methods mentioned deliver good results, but only for the case where neither the weapon nor the target object moves. If the weapon moves, the projectile flight path is influenced by this movement. If the target object moves, it can happen that after the projectile flight time the target object is already no longer at the projectile point of impact.
Up to now, the firing guidance solution is determined in the indirect or direct aiming and in the presence of a relative movement between the weapon and the target object in such a way that a plurality of pairs of values are provided for the azimuth and elevation. For these values, the movement differential equations are then solved by the methods of the state of the art until the firing guidance solution is found. The drawback for proceeding in this manner is that a plurality of pairs of values must be provided or prescribed for azimuth and elevation until a firing guidance solution is found. The calculation time thus required for the frequent solution of the movement differential equations makes a practical use of the firing with this method more difficult when an arbitrary relative movement is present between the weapon and the target option.
It is an object of the present invention, white solving the movement differential equations as few times as possible, to determine a firing guidance solution in the indirect or direct aiming and in the presence of an arbitrary relative movement between the weapon and the target object.